US3652842A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Area measurement
Assignee: Individual
•
Filing: 1970-02-05
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Granted: 1972-03-28
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Expires: 1990-02-05
Abstract
Abstract Apparatus for measuring an unknown area within a predetermined area, comprising: a pointer movable over the predetermined area by an operator to track the boundary of the unknown area; first and second means movable with the pointer to define co-ordinates for the pointer position within the predetermined area, the first such means generating first electrical signals at regularly spaced intervals along one co-ordinate axis to represent a graticule, and the second such means generating second electrical signals proportional to the spacing of the pointer position along the other co-ordinate axis from a reference position; means for interrogating the second signals in response to each of the first signals as the unknown area boundary is tracked; and means for summing the interrogated second signals to indicate the unknown area.
Inventors
- 👤 John Ernest Lewin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:43
CPC Classifications
G; G06; G06K; G06K11/00; G06F; G06F7/00; G06F7/60; G06F7/64; G06F7/66; H; H03; H03M; H03M1/00; H03M1/12; H03M1/22; H03M1/24; H03M1/28; H03M1/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
210 words
Apparatus for measuring an unknown area within a predetermined area, comprising: a pointer movable over the predetermined area by an operator to track the boundary of the unknown area; first and second means movable with the pointer to define coordinates for the pointer position within the predetermined area, the first such means generating first electrical signals at regularly spaced intervals along one co-ordinate axis to represent a graticule, and the second such means generating second electrical signals proportional to the spacing of the pointer position along the other co-ordinate axis from a reference position; means for interrogating the second signals in response to each of the first signals as the unknown area boundary is tracked; and means for summing the interrogated second signals to indicate the unknown area; wherein said first means includes a digitiser for generating said first signals, means for defining a predetermined counting period in response to each of said signals, and wherein said second means includes a variable frequency oscillator for generating said second signals, an accumulator to count said second signals during each of said counting periods; and means to inhibit counting of said second signals by said accumulator for a predetermined relatively low count value at the beginning of each of said counting periods.
Claim 2
Dependent Claim
210 words
Apparatus for measuring an unknown area within a predetermined area, comprising: a pointer movable over the predetermined area by an operator to track the boundary of the unknown area; first and second means movable with the pointer to define coordinates for the pointer position within the predetermined area, the first such means generating first electrical signals at regularly spaced intervals along one co-ordinate axis to represent a graticule, and the second such means generating second electrical signals proportional to the spacing of the pointer position along the other co-ordinate axis from a reference position; means for interrogating the second signals in response to each of the first signals as the unknown area boundary is tracked; and means for summing the interrogated second signals to indicate the unknown area; wherein said first means includes a digitiser for generating said first signals, means for defining a predetermined counting period in response to each of said signals, and wherein said second means includes a variable frequency oscillator for generating said second signals, an accumulator to count said second signals during each of said counting periods; and means to inhibit counting of said second signals by said accumulator for a predetermined relatively low count value at the beginning of each of said counting periods.
Claim 3
Dependent Claim
56 words
Apparatus according to claim 1 comprising a normally closed first gate connecting said oscillator and said accumulator, and a counter, normally held at a first predetermined count state, but responsive to said oscillator during a counting period to attain a second predetermined count state representing said low count value and thereupon to open said first gate.
Claim 4
Dependent Claim
67 words
Apparatus according to claim 2 comprising a first monostable device response to each of said first signals to generate a pregating pulse, a second monostable device responsive to the trailing edge of each of said pulses to generate a predetermined counting period signal to activate said counter for counting, and a second gate responsive to said second count state of said counter to open said first gate.
Claim 5
Dependent Claim
29 words
Apparatus according to claim 3 comprising a third normally open gate connecting said oscillator and said counter, but closed in response to said second count state of said counter.
Claim 6
Dependent Claim
29 words
Apparatus according to claim 3 comprising a coincidence detector responsive to said pre-gating pulses and said counting period signals, and an alarm indicator activated by operation of said detector.
References Cited (Backward Citations)
US3103578A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-28 | 1975-09-27 | 1976-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-28 | 1979-09-27 | 1980-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-28 | 1983-09-27 | 1984-03-28 | $7700.00 | Window Closed / Lapsed |